Train Electrics

Question 1

What Main Res. pressure do you need to raise Pantographs?

Answer 1

700kPa

Question 2

If Main res. pressure is insufficient how will the pantographs raise?

Answer 2

110vDC power from batteries powers the auxiliary compressor

Question 3

Where are auxiliary compressors located?

Answer 3

DMp cars

Question 4

Once DMp pantos are up, what main res. pressure will Mp pantos raise?

Answer 4

400-450kPa

Question 5

What is the purpose of the HV Box?

Answer 5

It supplies the Vehicle Traction System and Auxiliary Power system

Question 6

What is in the HV Box?

Answer 6

HSCB

Harmonic Wave Detection Device
(line inductor)

Question 7

What does the Harmonic Wave Detection Device do? (HWDD)

Answer 7

Filters the power coming from the traction system or overhead wire

Automatically cuts power to Traction and Auxiliary inverters if pre-set threshold of harmonic frequency is exceeded for 2 seconds or more

Question 8

What do the Auxiliary Inverters do?

Answer 8

Convert 1500vDC into 415vAC for

Battery charger
Air compressors
Traction Cooling system
HVACs

… and 240vDC to cab and saloon GPOs

Question 9

What does the battery charger do?

Answer 9

Converts 415vAC into 110vDC that charges batteries and provides power to train

Question 10

Where are the Traction Inverters located?

Answer 10

In the Variable Voltage Variable Frequency (VVVF) cabinet

There are two in each VVVF

Question 11

What do the Traction Inverters do?

Answer 11

Convert 1500vDC into Variable 3 phase AC

Question 12

What is the path of the power through the traction system?

Answer 12

Overhead

HSCB

TCU

Traction Motors

Question 13

What do the brake resistors do?

Answer 13

Absorb energy from braking and dissipate the heat

Question 14

What is APS?

Answer 14

Auxiliary Power Supply

Question 15

What does the APS consist of? (4)

Answer 15

Auxiliary Inverter

MV Box

Battery Box

Battery Charger

Question 16

What does MV Box do?

Answer 16

Maintains 415vAC

Question 17

What 415vAC equipment do we need to know about?

Answer 17

Battery Chargers

Air Compressors

Traction Equipment Cooling Systems

HVAC

Question 18

What happens if a Battery Charger fails?

Answer 18

The battery set will be charged via other Battery Chargers

Question 19

What are Permanent Loads?

Answer 19

Always connected to battery, whether cab is activated or not

Question 20

What are Non-Permanent Loads?

Answer 20

Only obtain power from battery set when the cab is activated

Question 21

What are Emergency Loads?

Answer 21

Either Permanent or Non-Permanent loads that have power during emergency conditions when Battery Charger fails or loss of overhead

Question 22

What things are affected during emergency conditions, i.e. under battery power?

Answer 22

Saloon lighting will reduce to 50% after 10 minutes

HVAC fresh air fan operates for at least 2 hours

Saloon doors operate as normal

Question 23

Which CBs will cause the train to fail?

Answer 23

Cab Activation

Traction Control

Emergency Brake Loop Power Supply

Brake Control Supply

Question 24

How many times are drivers allowed to reset a tripped CB?

Answer 24

Maximum of 2 times

Question 25

When will Safety Loop open and emergency brake apply? (9)

Answer 25

MCH to emergency

Pilot valves not set

ESB pressed

Trip activated

Vicers activated

MR falls below 600kPa

Towing unit demand for emergency brake

Safety system bypass reminder timeout

Train separation

Question 26

How do you reset the Safety Loop?

Answer 26

Stationary for more than 3 seconds

Fix reason for emergency brake application

MCH to MAX BRAKE

Reverser to NEUTRAL

Question 27

How will you know if there is fire?

Answer 27

Internal and external smoke detectors